The goal of this project is to use magnetic resonance imaging (MRI) to examine the natural history and potential therapeutic approaches in multiple sclerosis (MS). Emphasis has been placed on investigation of the early MS lesion which is characterized by enhancement on Tl weighted MRI images following administration of gadolinium-DTPA. Results from initial studies have indicated that MS can be an active disease, even during periods of remission in the early relapsing-remitting phase of the illness. Frequency of gadolinium-enhancing lesions has been examined in a series of patients with mild early MS. Monthly MRIs done longitudinally have been used to determine the optimal approach for using MRI as an outcome measure in MS. Possible correlations between clinical changes and both the frequency and area of gadolinium-enhancing lesions has been examined in order to determine if relationships between disease activity and changes on MRI exist.